This invention relates generally to heavy duty transport vehicles for carrying heavy to massive loads on any of the widely varying roadway surfaces and, more specifically, to a dolly for use with such vehicles which is self-steerable in response to the load thereon.
Land vehicles for carrying heavy to massive loads and vehicular components therefor are disclosed in U.S. Pat. Nos. 4,453,734; 4,460,194; 4,468,048; 3,438,652 and 3,439,630. Generally, these patents disclose various vehicles, suspension systems for vehicles and wheel/axle units for vehicles. Operator controllable steering for trailer-type vehicles for hauling heavy to massive loads is disclosed in U.S. Pat. No. 4,468,048.
Despite the refinements and improvements in the art concerning heavy duty transport vehicles, there still are some significant problems, particularly when intended payloads approach the very heavy or massive level. Some of these difficulties include: The vehicles used for transporting very heavy loads generally are massive themselves, and, in fact, may reach tremendous sizes; providing a vehicle with optimal handling and maneuverability characteristics; conforming to vehicular weight and weight distribution requirements imposed by jurisdictions through which a vehicle might pass during a long distance trip; and, conforming a vehicle's handling and maneuverability characteristics to an optimum level relative to the type of road surface upon which the vehicle is being operated.
A coinventor of the present invention, James McGhie, is the inventor or coinventor of a number of inventions related to heavy duty transport-type vehicles. For example, he is the coinventor of U.S. Pat. No. 4,943,078, issued Jul. 24, 1990. That application is directed to providing a heavy duty transport vehicle having hydraulically suspended, steerable, independent wheel and axle units which address some of the previously noted difficulties associated with vehicles used for transporting heavy to massive loads.
Typically, such vehicles include at least one tractor, a front tractor-drawn jeep, a front carriage, a rear carriage and a load unit disposed therebetween. The carriages and jeep are supported by a plurality of wheel/axle units. A load or load unit generally has forwardly and rearwardly projecting goosenecks attached thereto for connection to respective fifth-wheel couplers on the front and rear carriages. Over all vehicle length may reach and exceed 200 feet, exacerbating some of the problems noted above.
The present invention is directed to further improving transport vehicles for transporting heavy to massive loads.